The Casio DR-T120 is a printing calculator that does all basic calculations, displays up to 12 characters and prints up to eight lines a second. The calculator uses a thermal print head and thermal paper to eliminate the need for printer ribbons. The DR-T120 does not print on regular paper, but uses a 2 1/4 inch or 58mm wide roll of thermal paper that reacts to heat to display printed data. It is designed for high volume office use and for easy paper roll replacement.

Open the paper roll cover by lifting the cover from the front. The cover will snap open and lift towards the back of the calculator.

Remove the spool from the used paper roll if one is in the paper roll compartment.

Loosen the paper end edge from the new paper roll. The end of the paper will be taped or sealed with a sticky material. The paper end edge must be loose. Unroll the loose end 1 to 2 inches from the roll.

Place the paper roll in the compartment with the loose end towards the front of the calculator and coming from the underside of the roll.

Close the paper cover, making sure the loose end of the paper roll is sticking up through the paper slot in the cover. This aligns the paper for the thermal print head.